Download 5-Thoacolumbar spine

Life is 10% what happens to you and 90%
how you react to it.
Charles R. Swindoll
OBJECTIVES
At the end of the lecture, students should be able to:
 Distinguish the thoracic and lumbar vertebrae from
each other and from vertebrae of the cervical region
 Describe the characteristic features of a thoracic and
a lumbar vertebra.
 Compare the movements occurring in thoracic and
lumbar regions.
 Describe the joints between the vertebral bodies and
the vertebral arches.
 List and identify the ligaments of the intervertebral
joints.
Thoracolumbar Spine
Curves of the vertebral column
can be divided into:
Primary Curves:
Thoracic & Pelvic
Secondary curves:
Cervical & Lumbar
Note: The curvatures in Thoracic and lumbar spine.
Thoracic vertebrae
Most thoracic
vertebrae are typical,
have bodies, vertebral
arches and seven
processes for
muscular and articular
connection.
2 Transverse process
2 Superior articular process
2 inferior articular process
1 Spinous process
Note: A “typical” vertebra is made up of an anterior vertebral body and a posterior vertebral arch, more or less the
same to the rest. While the “atypical” vertebrae such as the 2 found in cervical region defy the norm.
Characteristics of Thoracic
Costal facets are present
The spines are
on the transverse
vertebrae
long and inclined
processes for articulation
with the tubercles of the
ribs (T11 and 12 have no
facets on the transverse
process).
Costal facets are present on
the sides of the bodies for
articulation with the heads
of the ribs.
downwards.
The vertebral
foramen is small and
circular.
The body is medium size
and heart shaped.
The superior articular processes bear facets that face backwards and laterally, where the
facets on the inferior articular process face forward and medially. The inferior articular
process on the 12th vertebra face laterally, as do those of the lumbar vertebrae.
Process : A pointy projection
Facet : Small flat surface
Tubercles : a small rounded projection
Characteristics of typical lumbar
The Spinous process are
The laminae are
vertebra
short, flat, and
thick .
quadrangular and project
backwards.
The vertebral foramina
are triangular.
The body is large and
kidney shaped.
The transverse
process are long and
slender.
The Pedicles are strong
and directed back wards.
The articular surfaces of the superior articular processes face medially, and those
of the inferior articular processes face laterally.
Foramen : opening or hole.
Slender : Thin
Now compare between and notice the major
differences between the two.
JOINTS BETWEEN TWO VERTEBRAL BODIES:
1-It is a cartilaginous
joint.‫غضروفي‬
2-The upper and lower surfaces
of the bodies of adjacent
vertebrae are covered by thin
plates hyaline cartilage.
3- Sandwiched between the
plates of hyaline cartilage is an
intervertebral disc of
fibrocartilage .
4- collagen fibers of the disc
strongly unite the bodies of the
two vertebrae.
JOINTS BETWEEN TWO
VERTEBRAL ARCHES:
Consist of synovial joints
between the superior and
inferior articular
processes of adjacent
vertebrae.
INTERVERTEBRAL DISCS:
• The intervertebral discs are responsible for one
fourth of the length of the vertebral column .
• They are thickest in the cervical and lumbar regions,
where the movements of the vertebral column are
greatest unlike the thoracic region which is LESS
THICK and has less movement .
• Each disc consists of a:
• Peripheral part: the anulus fibrosus, composed of
fibrocartilage .
• Central part : the nucleus pulposus, a mass of
gelatinous material containing a large amount of
water, a small number of collagen fibers, and a few
cartilage cells.
• No discs between the first & second cervical
vertebrae or in the sacrum or coccyx.
FUNCTION OF THE INTERVERTEBRAL DISCS:
1-Allow vertebra to rock forward or backward on
another like flexion and extension of vertebral
column.
2- Serve as shock absorbers when the load on the
vertebral column increased, as when one is jumping
from a height.
Sometimes, the annulus fibrosus ruptures,
allowing the nucleus pulposus to herniate
and protrude into the vertebral canal,
where it may press on spinal nerve roots,
spinal nerve, or even spinal cord.
LIGAMENTS
•The anterior and posterior longitudinal
ligaments run as continuous bands down the
anterior and posterior surfaces of the vertebral
column from the skull to the sacrum
The anterior longitudinal ligament
The posterior longitudinal ligament
wide and strongly
weak and narrow
attached to the front and sides of
the vertebral bodies and to the
intervertebral discs.
attached to the posterior borders of
the discs
Ligaments;
hold the vertebrae firmly together
Produce a small amount of movement
LIGAMENTS
Ligamentum
flavum:
connects
the laminae
of adjacent
vertebrae
Interspinous
ligament:
connects
adjacent
spines
Supraspinous
ligament: runs
between the tips of
adjacent spines
Intertransverse ligaments:
run between adjacent
transverse processes
MOVEMENTS OF THE THORACOLUMBAR SPINE
The following movements are possible on the spine:
1.
2.
3.
4.
5.
flexion,
extension
lateral flexion
Rotation
Circumduction = circular movement
The type and range of movements depend on:
Thickness of the intervertebral discs
Shape and direction of the articular
processes.
In the thoracic region, the ribs, the costal cartilages, and the
sternum severely restrict the range of movement.
Flexion & Extension Lateral flexion
Extensive in the lumbar regions Restricted in the thoracic
regions
Rotation
Extensive in the thoracic regions Less extensive in the lumbar
regions
MUSCLES PRODUCING MOVEMENTS
Thoracic Region
Rotation produced by semispinalis and rotator muscles, assisted
by the oblique muscles of the anterolateral abdominal wall.
Lumbar Region
Flexion
produced by the rectus abdominis and the psoas muscles.
Extension
produced by the postvertebral muscles.
Lateral flexion
produced by the postvertebral muscles, the quadratus lumborum, and the oblique
muscles of the anterolateral abdominal wall. The psoas may also play a part in this
movement.
Rotation
produced by the rotator muscles and the oblique muscles of the anterolateral abdominal
wall.
Vertebra L5
•
•
•
•
The largest movable vertebra.
It has massive body and thick transverse processes.
It carries the weight of the whole upper body.
The L5 body is largely responsible for the lumbosacral
angle between the long axis of the lumbar region of the
vertebral column and that of the sacrum.
• Body weight is transmitted from L5 vertebra to the base
of the sacrum, formed by the superior surface of S1
vertebra
Vertebra L5
The fifth lumbar vertebra is by far the
most common site of spondylolysis
(defect in the pars interarticularis of the
vertebral arch) and Spondylolisthesis (the
forward displacement of a vertebra).
Normal Curvatures in Spine
• Primary (Thoracic & Pelvic) .
• Secondary (Cervical & Lumbar) .
Abnormal Curvatures of spine :
• Exaggerated Thoracic curvatures (Kyphosis)
• Exaggerated lumbar curvature (Lordosis)
• Lateral curvature of spine. (Scoliosis)
Scoliosis
Kyphosis
Lordosis
 SUMMARY
• There are 12 thoracic vertebrae that articulate with the rib cage .
• There are 5 lumbar vertebrae that are strong and highly flexible.
• Superior articular processes facets face backward and laterally, where
as the Inferior articular processes face forward and medially.
• Cartilaginous joint between the bodies of the vertebrae and synovial
joints between the vertebral arches .
• Only movement in the thoracic region is rotation, where as the
lumber region has a variety of movements .
Type and range of movements
Thoracic
region
Lumbar region
Rotation
(least extensive)
Flexion
Extension
Lateral flexion
Rotation
(extensive)
flexion, extension
and lateral flexion
(restricted)
Don’t forget
• No discs between the first & second cervical vertebrae and in the
sacrum or coccyx.
• Rupture o f the Annulus fibrosus may cause the nucleus pulposus to
herniate pressing on the surrounding nerves.
• Normal curvatures in thoracic and lumbar spine .
Video:The spinal ligaments
https://www.youtube.com/
watch?v=GQ4193o5Q7Q
Video: Spine Anatomy 3D
animation
https://www.youtube.com/
watch?v=178XnTK5uHk
Application: Essential anatomy 5
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Quiz:
https://www.onlineexambuilder.com/thoracolumb
ar-spine/exam-48810
Group (2) Leader:
Fahad AlAbdullatif
Group(2) members:
Faisal AlJammaz
Faisal AlYahya
Saad AlMotairi
Hassan AlShammasi
Abdulwahab AlMansour
Talal AlEbewani
Abdullah AlMushawah
Ibrahim AlSuhaim
Fahad AlHomaid
Boudor Julaidan
Editing Team (boys):
Khaled Al Jedia
Rawhdan Al Nahdi
Abdulwahab Sanari